Attachment for pneumatic riveters and similar tools.



H. B. GRINER.

ATTACHMENT FOR PNEUMATIC RIVETERS AND SIMILAR TOOLS.

APPLICATION FILED DIJ0.16, 1913.

97 545 Patented May 19, 1914.

W INVENTOR ATTORNEYS HARRY B. GRINER, OF PHILADELPHIA, PENNSYLVANIA.

ATTACHMENT FOR PNEUMATIC RIVETERS AND SIMILAR TOOLS.

Specification of Letters Patent.

Patented May-19, 1914.

Application filed December 16, 1913. Serial No. 807,027.

To all whom it may concern Be it known that I, HARRY B. GRINER, a citizen of the United States, residing in the city and county of Philadelphia, State of Pennsylvania, have invented a new and useful Attachment for Pneumatic Riveters and Similar Tools, of which the following is a specification.

In pneumatic riveting hammers of the type now commonly employed, wherein the piston has a length of stroke equal to or greater than its own length, and reciprocates several hundred times a minute and imparts a hammering blow to the working tool, rivet set or button set, a comparatively high pressure of the motive fluid is employed and the rivet set or piston is liable to be accidentally impelled from the tool cylinder and either lost by dropping to the ground or into the water, when the implement is used on bridge work, and in addition it sometimes happens that bystanders or operators are struck by the rivet set or the piston which may be impelled from the tool cylinder with great velocity and serious injury is thereby caused. The liability of danger from these causes has become recog nized to such an extent in some States that legislation has already been passed requiring pneumatic riveting hammers to be equipped with a tool retainer of some character and the present invention relates to a novel construction of such a pneumatic tool retainer designed to be employed in conjunction with pneumatic tools of the rivcter type, wherein the piston may or may not have a length of stroke greater than its own length.

In the practical application of my invention, I prefer to employ a rivet set which is removed from the actual impact of the reciprocating hammering piston either by means of a threaded or driven plug locked or inserted within the forward end of the tool cylinder, which enables my invention to be applied to the cylinders of pneumatic hammers as already constructed or, if desired, the forward end of the cylinder may be left solid or substantially closed during the manufacture thereof so that when the operative parts of the tool are assembled, it will be absolutely impossible for the piston to be in'ipclled therefrom, the button or rivet set being held in proper relation to the forward end of the cylinder by means of a spring clip or button set or rivet set retainer of the usual construction.

With the above and other objects in view which will more clearly appear from the detailed description, my invention consists of a novel construction of a pneumatic tool piston retainer or attachment for pneumatic riveters or similar tools and novel means for securing the same with respect to the barrel or cylinder of the pneumatic tool.

My invention further consists of a novel construction of a button set, wherein the shank portion of the same is entirely removed or dispensed with, so that by my novel invention, I am enabled to utilize old button sets, wherein the shanks thereof have been partly or wholly broken or fractured.

It further consists of other novel features of construction, all as will be hereinafter fully set forth.

For the purpose of illustrating my invention, I have shown in the accompanying drawing a preferred embodiment which is at present preferred by me, since the same will give in practice satisfactory and reliable results, although it is to be understood that the various instrumentalities of which my invention consists can be variously arranged and organized and that my invention is not limited to the precise arrangement and organization of these instrumentalities as herein shown and described.

Figure 1 represents a side elevation partly in section, of an attachment for a penumatic riveter or other tool or a penumatic tool piston retainer, embodying my invention, the latter being shown as applied to the well known Boyer riveter. Fig. 2 represents, on an enlarged scale, a sectional View of the forward end of the pneumatic tool cylinder showing my invention as applied thereto, in combination with a locking device which may be employed. Fig. 3 represents an end elevation of Fig. 2. Fig. 4 represents a side elevation partly in section of another embodiment oiaiiiy invention. Fig. 5 represents a perspective view of the novel button set, I employ.

Similar numerals of reference indicate correspond ng parts in the figures.

Referring to. the drawings, 1 designates the barrel or cylinder of a pneumatic rivet ing or other hammer, the same being provided with a grasping handle 2, piston chamber 3 and the reciprocating piston 4 therein, which as generally constructed comprises a plain cylindrical bolt of substantially uniform diameter throughout its length. I have omitted to show or describe the ports for the inlet and exhaust of the motive fluid, as the same, per 56, form no part of my invention which latter in its broad aspects may be employed in conjunction with any type of pneumatic hammering or riveting tool.

In pneumatic hammers as now commonly constructed, the forward end of the same is generally open or unobstructed except when the shank of the button set or desired implement is inserted in position and in order to equip old tools of this character with my invention, I thread the forward end of the same as indicated at 5 and then insert a threaded plug 6 therein, having the forward end 7 thereof, flush or projecting slightly forwardly of the end 8 of the tool cylinder 1, as will be best understood from Fig. 2. The plug (3 is preferably caused to engage the threaded end of the tool cylinder so as to fit as tightly or snugly as possible therein and in order to prevent the same from becoming disengaged therefrom, through the vibration caused by the impact of the hammering piston upon the rear end 9 of said plug, I employ a suitable locking device, one form of which is shown in Figs. 1, 2 and 3, wherein a suitable locking device is indicated at 10, and comprises the deflected terminal 11 having the straight member 12 and the curved portion 13 which terminatesin the inwardly turned portion 1 1 which engages a suitable recess 15 in the plug 6, as will be understood from Fig. 3.

By the employment of the above construction together with the locking device and its adjuncts, it will be seen that I completely close the forward end of the tool cylinder 1, so that the piston at is positively prevented from shooting therefrom in case air is accidentally or inadvertently admitted in to the piston chamber 3, which sometimes happens through the workman or attendant accidentally kicking or hitting the thumb lever 30 of the grasping handle 2.

In my novel construction of button set I employ a device 22 having no shank or rearward extension thereon, said button set preferably having a flat face 16, which abuts againstthe face 7 of the threaded plug, the button set being provided with the groove 17 which is engaged by the bent portion 18 of the clip or retaining device 19, which has an inturned edge 20 engaging with the groove 21, the button set retaining device being in other respects of the usual construction and the forward end of the button set or rivet set 22 being fashioned or shaped to engage the heated rivet during the heading thereof, as is customary.

The foregoing construction seen in Figs. 1, 2 and 3 shows one embodiment of my invention as applied to cylinders of existing rivetingor other hammers, and it is obvious that I may secure the closure or plug 6 in position by other means, for example, by a driving fit or the employment of any other suitable means for preventing disengage ment of the plug from the tool cylinder.

I11 Fig. at, I have shown my invention in the form in which it may be applied to the cylinders of new pneumatic'tools, wherein 23 designates the tool cylinder having the piston chamber 2st and the hammering piston l therein, of the same character, as that already described. In the construction seen in Fig. 4 I close the forward end of the cylinder, as indicated at the wall 25 but pro vide the port 26 therein for the insertion of a suitable tool to disengage the piston should it stick, said port 26 being closed by means of the threaded plug 27 which is screwed into the enlarged port 28.

The button set and clip or retainer therefor seen in Fig. at are of the same character or construction as already described with respect to Fig. 1 and I deem it unnecessary to repeat said description, except to point out that in this construction the rear wall or face 16 of the button set is placed directly against the forward flat end 29 of the tool cylinder 23, as will be seen from Fig. 4.

In both the embodiments of my invention, it will be seen that there is no possibility whatever of the hammering piston escap ing or being impelled from the forward end of the tool cylinder 1 or 93 under any conditions whatever, as said forward end of the tool cylinder is entirely closed and the impact of the hammering piston is received either upon the face 9 of the threaded plug 6 in the construction seen in Fig. 1 or in the construction seen in Fig. at upon the wall 25 of the cylinder It will furthermore be apparent that by the employment of my novel construction of button set seen in Figs. 1, 4; and 5, having no shank thereon, that I am enabled to use old broken button sets, having their shank or rearwardly projecting portion fractured, since it is only necessary to grind off such shank so that the button set or rivet set will appear as seen in Figs. 1, 4: and 5.

I have found from practical experience in the operation of my invention, that the vibrations incident to the rapid reciprocation of the hammering piston 4 are ,considerably reduced by the employment of my invention and the workman is therefore enabled to hold the tool up to his work with less fatigue than heretofore. Furthermore, I have found that by closing the end of the pneumatic tool cylinder great economy of air is effected, there being no escape or leakage possible past the rivet set shank, as now happens in the present type of riveting tion, by the use of my invention,'I amenabled to utilize broken rivet sets which have heretofore been discarded as useless, whereby a considerable saving in this item, which has heretofore been a total loss, is effected.

It will be understood that while I have shown my invention as being applied to pneumatic riveting hammers of the well known Boyer type, the same is capable of application to pneumatic rlveting or hamtools of other-types with equal facility and efiectiveness.

It will now be apparent that I have devised a novel and useful construction of an attachment for pneumatic riveters and similar tools which embodies the features of advantage enumerated as desirable in the statement of the invention and the above description, and while I have, in the present merln instance, shown and described a preferredv embodiment thereof which has been found in practice to give satisfactory and reliable Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. The combination of a pneumatic tool cylinder, having its forward end completely and rigidly closed, a button set having a groove therein, and a straight rear wall and means common to said cylinder and groove for retaining said button set against the forward end of said cylinder. p

2. A pneumatic tool cylinder having the forward end of its bore provided with screw threads, a threaded ug in engagement with said screw threa s, and a locking de vice for preventing said plug from becoming disengaged from said tool cylinder.

- 3. A pneumatic tool cylinder having the forward end of its bore provided with screw threads, a threaded plug. in engagement with said screw threads, and a locking device for preventing said plug from becoming disengaged from said tool cylinder, in

combination with a button set unprovided with a shank and having its rear wall held against the forward end of said threaded plug. a

4:. The combination of a pneumatic tool cylinder having a complete and rigid closure at the forward end of its bore, a grasping handle secured to the rear end of said cylinder, a shankless rivet set, and means for holding the rear wall of said rivet set in operative engagement with the forward end of said cylinder.

HARRY B. GRINER. Witnesses:

H. S. FAIRBANKS, C. D. MoVAr.

WWI-W 

